Folding combination step ladder and stool



1962 c. ROUSE 3,059,722

FOLDING COMBINATION STEP LADDER AND STOOL Filed Dec. 16, 1960 2 Sheets-Sheet 1 INVENTOR. CALI/HY fo 5c ,4 rrop/vsys Oct. 23, 1962 c. ROUSE 3,059,722

FOLDING COMBINATION STEP LADDER AND STOOL Filed Dec. 16, 1960 2 Sheets-Sheet 2 IN V EN TOR. C4 w/y @OUSE A frag/W575 United States Patent 3,059,722 FOLDING COMBINATION STEP LADDER AND STOOL Calvin Rouse, 8726 16611: St., Jamaica, N.Y. Filed Dec. 16, 1960, Ser. No. 76,312 2 Claims. (Cl. 182-33) This invention relates to folding furniture and more particularly to a folding combination step ladder and stool. Conventional forms of folding step ladders and folding stools or combinations thereof are generally bulky articles of furniture which rarely save enough space even when folded to make their foldable characteristic worthwhile.

An even more common problem in the same general area of step ladder and stool furniture is that shipping costs are high because of the bulk involved in shipping assembled articles of this sort. It is not considered a satisfactory solution to this problem to ship such articles in an unassembled form because of consumer resistance to difficult assembly procedures.

It is an object of my invention to provide a combination step ladder and stool which can be readily folded so as to be extremely compact for storage. It is another object of my invention to provide a combination step ladder and stool which can be shipped economically in its folded position, and it is a particular object to provide such an article which can be shipped by Parcel Post service of the US. Mail, which has strict requirements governing the maximum size of articles acceptable for mailing. It is still another object to provide a combination step ladder and stool which can be shipped to the ultimate consumer in a completely assembled form, ready for use as soon as unfolded. It is a further object to provide a combination step ladder and stool of a simple construction which is strong and stable and therefore safe to use.

Briefly, my invention embodies a seat and back set upon a pair of-crossed U-shaped members which form legs. The U-shaped members are pivotally connected to each other and, by hinges, to the seat. Steps are also pivotally connected to the legs, and can be folded within the legs. When the legs are folded together and the steps are folded within the legs, the seat and back are foldable over them.

Other objects and features may be inferred from the following description of specific examples of this invention, illustrated by the accompanying drawings in which:

FIG. 1 is a perspective view of a combination step ladder and stool of my invention in its unfolded position, with a seat of the stool shown in shadow form;

FIG. 2 is a perspective view of a combination step ladder and stool of my invention in a semi-folded position;

FIG. 3 is a perspective view of a combination step ladder and stool of my invention in its completely folded and most compact position; and

FIG. 4 is a detailed view of a mechanism adapted to secure the backreston the stool in an upright position when the stool is in its unfolded position. I

In FIG. 1, a combination step ladder and stool is shown generally at 10. A first U-sha-ped frame 11 of tubular metal construction comprises front legs 12 and a rear cross portion 13. A second U-shaped frame 14 comprises rear legs 15 and a front cross portion 16 and is smaller than frame 11. The frames 11 and 14 are pivotally connected at the points where they cross each other, more than midway on their respective leg portions, by rivets 17. Back hinges 18 and 19 are pivotally connected to the rear cross portion 13 of the frame 11. Brackets 20 and 21 respectively are fixed by conventional means (not shown) to hinges 18 and 19 respectively. A seat 22 (shown in FIG. 1 in shadow form) is fixed by conventional fastening means (not shown) to brackets 20 and 21. A bracket 23 is fixed by conventional fastening means (not shown) to approximately the center portion of the seat 22. A metal strap hinge 24 is pivotally connected at 25 to the bracket 23 and is pivotally connected at 26 to the cross portion 16 of the frame 14. The distance between pivot point 25 and pivot point 26 is less than the distance between pivot point 25 and cross portion 13 of frame 11 by an amount at least equal to the diameter of the tubular frame material used. The seat 22 consists in a preferred embodiment of a base 27 and upholstery 28 of conventional materials.

In the preferred embodiment a latch is attached to the underside of the seat 22 near the forward edge thereof adapted to latch the seat to the cross portion 16 to hold the seat in the position shown in FIG. 1.

A back, indicated generally at 29, consists of a U-shaped back frame 30 with angled ends 31 and 32 and connecting members 33. The angled ends 31 and 32, respectively, are pivotally connected to the brackets 20 and 21, respectively by rivets 34. Angled ends 31 and 32 are broad enough so that they rest on brackets 20 and 21 when the back 29 is in an upright position, to limit back-wards pivotal movement of the back 29.

A hole 35 is located in angled end 31. Another hole 36 is located in bracket 20 and is aligned with hole 35 when the back 29 is upright (holes 35 and 36 are most clearly shown in FIG. 2). A retractable stud assembly, indicated generally as 37, is fixed to hole 35 to prevent pivotal movement of the back 29 when the back 29 is upright and hole 36 is engaged with the stud assembly 37.

The retractable stud assembly 37 is shown most clearly in FIG; 4. A tubular sleeve 38 is aligned with and fixed to hole 35. A stud 39 is inside and aligned with the tubular sleeve 38 and projects past the hole 35 engaging hole 36 when the back 29 is erect. A cap 40 is fixed to the stud 39 to permit manual withdrawal of the stud 39 from the hole 36. A spring (not shown) is inside the sleeve 38 and operates to keep the stud 39 engaged with hole 36, when the back 29 is erect, unless manually pulled out. A bumper washer 41 engages the stud between tubular sleeve 38 and cap 40. The retractable stud assembly is used in a preferred embodiment of the invention so that someone who stands on one of the steps 44 and 49 and who holds onto the back 29 for balance will not cause the back to pivot forward. However, any method of holding the back upright during use may be used.

A grooved lip 43 is located in angled end 31 so that as the chair is unfolded and the back 29 is pivoted to an erect position, the lip 43 will push the stud 39 out of the way until the hole 35 is aligned with stud 39 at which point the spring 41 causes the stud 39 to engage the hole 35 and hold the back 29 erect.

An upper step 44, formed of stamped metal in a preferred embodiment, is fixed by screws 45 and rivets 46 to upper support bars 47, having angled end portions 48. The angled end portions 48 are respectively pivotally connected to the rear legs 15 by rivets 49, at a point below the rivets 17 which form the pivotal connection of the frames 11 and 14. A lower step 50, also formed of stamped metal in a preferred embodiment, is fixed by screws 45 to lower support bars 51, having angled end portions 52. The angled end portions are respectively pivotally connected to the rear legs 15 by rivets 53 at a point below the rivets 49 which form the pivotal connection of the upper support bars 47 and the rear legs 15.

When the chair is fully opened as in FIGURE 1, the outer edge 54 of lower step 50 does not overhang the line between the lower ends of the two front legs 12 to Y assure stability when used as a ladder.

A cross bar 55 is welded between the front legs 12 in a position selected so as to limit downward pivotal movement of the lower support bars 51 and hold the lower step 50 in 'a horizontal position when the support bars 51 are resting on the cross bar 55.

Patented Oct. 23, 1962 Each upper support bar 47 is connected to corresponding lower support bar 51 on the same side by a support element 56, which is pivotally connected to the upper supportbar 47 by a rivet 46 and to the lower support bar 51 by a rivet 57. The support bars 47, support bars 51, support elements 56 and rear legs 15 approximately define parallelogr'ams, and the pivotal interconnections cause any pivotal movement of one step and its support bars to be coupled to the other steps and its support bars. In any position of the steps 44 and 50, their substantially parallel relationship willbe maintained due to the parallelogram defined by the structural elements and their pivot points.

In order to fold the stool 11 from the position shown in FIG. 1 to the position shown in FIG. 3, the steps 44' and 50 are pivoted from the horizontal position shown in FIG. 1 to the position between the frame 1 shown in FIG. 2: As described above, pivotal movement of either stepi i and 50 is coupled to the other step, so that both can be folded up between the frame 14 with one movement. The lower support bars 51 frictionally engage support elements 56 when folded as shown in FIG. 2 to retain steps 44 and 50 in the folded position against gravitational force. Due to the shapes of the angled end portions 43 and 52, the steps 44 and 50 and support bars 47 and 51 will occupy a position predominantly behind the frame 14 when they are in their extreme folded position.

After the steps 44 and 50 are folded, the seat 22 is lifted to the position shown in FIG. 2, and the frames 11 and 14 are pivoted together. When the frames 11 and 14 are in the extreme folded position, as shown in FIG. 3, the seat 22 is folded on the pivotal connections 22 and 23 over the frames 11 and 14 and the back 29 is then pivoted down over the seat 22. The cross portion 16 of the frame 1 1 is directly under the cross portion 13 of frame 11. Frame 14 fits entirely within frame 11 so as to occupy a minimum of space. The angled ends 31 and 32 of the back frame 30 permit the back 29 to lie flat over the folded seat 22.

In its unfolded position, a preferred embodiment of the stool 1.0 has the following dimensions: total height 37 inches, seat height 24 inches, depth 23 inches, and width 14 /4 inches. All the foregoing dimensions are within a normal range for conventional stools and folding step ladders. However, in a folded position, it is a feature of my invention that the longest dimension plus the peripheral dimensions of a cross section is 70 inches, well within the maximum limit of 72 inches, which is the largest total of longest dimension plus cross sectional peripheral dimensions acceptable for mailing as Parcel Post by the US. Post Office.

The folding combination step ladder and stool of my invention is ideally suited to a tubular metal construction, but it could as well be constructed of wood, plas-v tic or non-tubular metal structural elements. Also, the seat may be upholstered or not as desired, and the back may be upholstered or not. 1

While one embodiment of the present invention has been shown and described, it is to be understood that certain changes and additions can be made by those skilled in the art Without departing from the scope and spirit of this invention I claim:

1. A folding combination step ladder and stool com prising a larger inverted U-shaped frame having leg portions and a cross portion; a smaller inverted U-shaped frame, having leg portions and a cross portion, fitted inside and pivotally connected to said larger inverted U'shaped frame at a point on the leg portions of each that is substantially closer to said cross portions than ends, pivotally connected to each of said vertical portions of said two back hinges at said ends so that said horizontal portion of said hinges obstructs backward rotation of said seat past an erect position; a bracket fixed to the central portion of said seat; a rigid, strapshaped hinge pivotally connected at one end to said center-of-the-seat bracket and pivotally connected at the other end to said front cross portion of said smaller frame, the length of said strap-shaped hinge from pivot to pivot being less than the distance between said center-of-the-seat bracket pivot point and the pivot line of said seat around said cross portion of said larger frame; two horizontal support bars for an upper step, each pivotally connected to the inside of a separate one of said rear legs of said smaller frame at a point below said pivotal connection ofsaid U-shaped frames; an upper step fixed to said upper step support bars; two lower step support bars, parallel to said upper step support bars and each pivotally connected to the inside of a separate one of said rear legs of said smaller frame; two vertically inclined upper step support bars, parallel to said rear legs of said smaller frame, each pivotally connected at one end to the inside of a separate one of said lower step horizontal support bars and pivotally connected at the other end to the inside of a separate one of said upper step horizontal support bars; a cross bar fixed between said front legs of said larger frame at a point to come into contact with the lower edges of said lower step support bars so as to obstruct downward rotation of said lower step past a horizontal position; and means to hold said back erect in the unfolded position.

2. A folding combination step ladder and stool as defined by claim 1 wherein said means to hold said back erect in the unfolded position is a retractable stud assembly comprising a sleeve fixed to said vertical portion of one of said back brackets, a spring loaded stud within said sleeve and projecting past said sleeve, a spring within said sleeve to maintain the stud in an extended position past the opening of said sleeve, a hole in said vertical portion of said bracket to receive the extended stud, a hole in the adjoining one of said vertical ends of said back located so as to align with said hole in said bracket when said back is erect to receive the extended stud; a cap attached to said stud at the non-extended end to permit manual removal of said stud from said hole in said back end; alip on the bottom edge of said vertical back end to engage said extended stud when said back is rotated to an erect position and to force said stud to a flush position with said hole in said bracket to permit the rotation of said back until said hole in said back and aligns with said stud.

References Cited in the file of this patent UNITED STATES PATENTS 

